Deep eutectic solvent-based microwave-assisted extraction of genistin, genistein and apigenin from pigeon pea roots

•Deep eutectic solvents were used as green extraction solvents.•Efficient and green extraction of flavonoids from pigeon pea root was optimized.•Deep eutectic solvent-based microwave-assisted extraction was developed.•The kinetics of DES-MAE process was investigated for the first time.

The purpose of the study was to develop a new deep eutectic solvent-based microwave-assisted extraction (DES-MAE) method for extracting the three major active compounds genistin, genistein and apigenin from pigeon pea roots. Optimal conditions for DES-MAE, proposed by the single factor and the Box-Behnken design (BBD) tests, were 30% of water in 1,6-hexanediol/ChCl (7:1, mol/mol) as the extraction solvent, microwave power 600 W, liquid/solid ratio 14 mL/g, temperature 80 °C and time 11 min. The yields of genistin, genistein and apigenin reached 0.449, 0.617 and 0.221 mg/g DW, respectively. The kinetics experiment showed the prominent advantages of DES-MAE such as higher extraction efficiency than other extraction methods. The present results showed that DES could be a kind of green solvent for fast and efficient extraction of the active ingredients from plant materials.